Microsoft: "20% of WGA failures not caused by pirated keys"

Oh, really? Turn that statistic around: Microsoft said that 20% of all Windows users who fail the WGA validation test are not using leaked or stolen keys.

So what is the reason for WGA rejecting the other 20% of Windows licenses? ComputerWorld apparently didn't ask, so I fired off an e-mail to Microsoft's PR agency, who passed along a response from Cori Hartje, Director of Microsoft Genuine Software Initiative:

While we will don't have specifics to share on other forms counterfeit installations, they mostly result from activities such as various forms of tampering and unauthorized OEM installations..